However, the Microsoft Store is non-committal as to the processor current customers will receive, merely referring to the Surface Pro 2's CPU as a "4th generation Intel Core i5 Processor" - a description which could refer to either model.

Given the lack of clarity on the website, PC Pro reader Jo Halfacre rang Microsoft in early January to confirm that the tablet would ship with the upgraded chip. "Having been assured that it was indeed the i5-4300 and no longer the i5-4200 processor, I proceeded to order a Surface Pro 2 128GB," she told us.

Yet when the tablet arrived it contained the older processor. She contacted Microsoft, and was told that the sales advisor she had spoken to previously had been mistaken, and that models using the i5-4300U weren't yet in stock.

"It was suggested to me that I wait a week or so and then call back, as they were expecting the tablets with the new processors to be available very soon," Halfacre said.

"So, on 6 February, I made the venture again and called Microsoft. Again I asked which processor was in the Surface Pro 2, and again I was absolutely assured that it was the i5-4300. I purchased one, and you already know the outcome of this: I received another Surface Pro 2 with an i5-4200 processor!"

When Halfacre complained to Microsoft for the second time, she learnt that the company had received "multiple complaints throughout the previous week that customers were receiving i5-4200 instead of i5-4300 processors".

"I now feel like I’m in limbo because I don’t feel that I can trust what I am told by anyone from Microsoft," she added. "I need a new tablet/laptop and I am two months done the line and still waiting!"

Microsoft hadn't returned our request for comment at the time of publication.